1. Field of the Invention
This present invention relates to friction rail skates. More specifically, the present invention relates to a friction rail skate positioned on a rail to disengage a railcar wheel from the rail, support the railcar wheel, and to frictionally slide along the rail under loads transmitted to the rail skate causing the railcar to slow and stop.
2. Description of the Related Art
Friction rail skates have been known for many years. Such friction rail skates are fabricated or cast as a single rigid body and commonly include a toe, lifter, or entry portion designed so that a railcar wheel will roll onto the rail skate until the railcar wheel engages an upwardly inclined ramp. Upon the railcar wheel becoming engaged with the rail skate, the momentum of the railcar will cause the rail skate to frictionally slide along the rail. Ultimately, the railcar will be stopped as a result of the rail skate frictionally sliding along the rail.
Various devices have been employed that use friction forces between the device and the rail it rests on to stop a railcar. Some of these have been set forth in U.S. patents. U.S. Pat. No. 842,679 sets forth a safety street-car brake intended for use as an emergency-brake should the motorman or operator of a car lose control of the same upon a declivity or sharp grade that employs shoes which are normally supported above the rails over which the car the travels, said shoes being quickly released by the motorman of a car to permit them descending to the rails where the wheels ride upon the shoes and cause a gradual retardation in the movement of the car, which eventually stops. U.S. Pat. No. 3,027,851 sets forth a device which engages the wheels of a railcar and stops it in which the weight of the car is first utilized to retard its movement and, if this is not sufficient, in which the car is stopped by an additional stop means located on the track. U.S. Pat. No. 4,498,561 sets forth a retractable wheel chock assembly for railway wagons that comprises the combination of a wheel chock designed to act on the flange of a wagon wheel, and a friction brake attached to the wheel chock and sliding along a guide rail mounted just outside the railway track on which the wagon is running U.S. Pat. No. 5,211,266 sets forth a rail skate where the shoe member has a longitudinal linear break that forms a line along its center to form a substantially V-shaped cross-section comprising a central high point and depending side portions produced substantially entirely from fabricated steel, and the shoe member is preferably formed of high strength, low alloy steel having a high yield strength. U.S. Pat. No. 6,978,865 sets forth a wheel-blocking device and in particular a safety chock for large wheeled vehicles and the chock may be also used as an emergency braking device at low speeds, similar to a rail skate but more efficient.
U.S. Pat. No. 5,211,266 discloses that a problem with known rail skates has been the bending or curling up of the toe portion of the rail skate due to heating of the underside thereof caused by the friction between the rail skate and the rail as the rail skate slides along the rail under the substantial weight of the railcar. The resultant heating of the underside of the toe portion of the rail skate causes that underside to expand, and as a result the toe portion of the rail skate has a tendency to curl up. If significant upward curling of the toe portion occurs, the rail skate can be rendered useless because a railcar wheel will not properly roll up onto the toe portion. It is well known that rail skates or skids are replaced when the toe portion is curled or broken.
U.S. Pat. No. 5,211,266 also discloses that prior art rail skates have been made substantially heavier in an attempt to reduce the above curling effect and provides a shoe member extending the entire length of the rail skate formed with a linear or longitudinal break to achieve a substantially V-shaped cross-section so as to distribute the heat to the two sides of the underside of the toe portions and, at the same time, increase the resistance of the toe portion to upward curling or bending. More specifically, the substantially V-shaped cross-sectional configuration extends the full length of the shoe element, including, in particular, throughout the length of the toe section which is the portion that is normally subject to upward curling due to heat generated during the sliding of the shoe on a rail.
The prior art has a number of shortcomings. Generally, the prior art thickens and changes or modifies the transverse cross-sectional shape of a rail skate and toe portion and teaches that a rail skate is fabricated or cast as a single rigid body. The prior art also does not provide a transverse division of the cast or fabricated single rigid body of a rail skate. Prior art rail skates art are not separable or provided with a replaceable or an interchangeable tongue to accommodate different wheel diameters. More specifically, U.S. Pat. No. 5,211,266 sets forth a rail skate fabricated as a single unit by rigid welds that continues to result in waste because it is not manufactured as a separate base and tongue where the base may be reused with a replacement or interchangeable tongue. Moreover, the prior art does not combine the benefits of a base and tongue that can be cast and assembled without any machining or welding.
3. Summary of the Invention
Accordingly, a need has arisen for a rail skate that overcomes the deficiencies in the prior art. Generally, in accordance with one embodiment, the present invention provides a rail skate that combines a base and tongue that may be easily assembled or dissembled with a mechanical connection. Specifically, the present invention provides a transverse division of the prior art rail skate into a base and tongue, and a system for making the base and tongue easily detachably connected or interlocked. Advantageously, the present invention provides a system for connecting the base to the tongue without thickening the toe portion and without requiring a special cross section to resist bending, curling, or breakage.
Accordingly, an object of the present invention is to provide a rail skate with a base and a tongue that can be easily manufactured and assembled without any additional machining or welding. It is also an object to make a rail skate that can be easily disassembled. In one embodiment of the present invention, the conventional rail skate is manufactured in two (2) cast parts: 1) a base and 2) a tongue. The base and tongue are detachably connected with a mechanical connection comprised of a hitch in cooperation with a receiver along with a post in cooperation with a wall and a receptacle. This mechanical connection is maintained under loads of a railcar wheel and improves contact between the rail and rail skate and minimizes structural bending of the rail skate.
Manufacturers, rail road employees, and others will find the present invention advantageous. Railroad yardmen will be provided with a lighter rail skate that may be hand carried as a base and a tongue. Railroad yardmen will also find that present invention offers configurations where no separate tools are required to assemble or disassemble the rail skate. Moreover, safety is an important aspect and operators and companies will find that making the rail skate where it can be easily disassembled reduces the risk of lifting injuries. Operators will not only find the present invention safer, but will find it more cost effective because it provides the tongue as a wear part that can be easily replaced. Rail road operators and companies will find that present invention is attractive from a cost perspective because unlike the prior art the base is reusable and the tongue is replaceable and interchangeable. Operators will also find the present invention cost effective because the base that may be interchanged with tongues of different configurations that accommodate rail car wheels of different sizes.
The present invention is also cost advantageous over the prior art. Specifically, the mechanical connection comprised of a hitch in cooperation with a receiver along with a post in cooperation with a wall and a receptacle does not require any alteration from the foundry and may be shipped direct to the end user saving the intermediate transportation and labor costs.
In addition to providing a detachably connected base and tongue, the present invention provides a modified ramp, incline, and toe portion of a rail skate; and converts the ramp into a cooling fin; and relocates the incline to the base. The cooling fin also advantageously relocates mass to an area to resist loads and reduce the size and weight of a rail skate while acting as a heat sink to dissipate heat from the tongue.
Other objects and advantages will become obvious to those skilled in the art from a review of the specification that other forms may be made within the scope of the invention.